Due to advances in communication systems, various wireless terminals have been introduced to consumers, such as companies and individuals.
A current mobile communication system has been affiliated with 3GPP, for example, Long Term Evolution (LTE), LTE-Advanced, and the like. Such a mobile communication systems are capable of transmitting and receiving a large amount of data at a high speed. Furthermore, the mobile communication systems are capable of transmitting, receiving, and processing various types of data, such as multimedia data, radio signal, and the like, as well as a voice data.
Accordingly, there is a desire for technology that extends the capacity of a User Equipment (UE) by utilizing small cells for the high speed and high capacity communication system.
In this instance, a UE may configure dual connectivity with a BS that provides a macro cell and a BS that provides a small cell, so as to transmit or receive data. The UE may configure at least one bearer with each BS.
The handover technology is an essential technology for supporting the mobility of a UE, and the handover technology is important to providing seamless communication services along the movement of the UE.
Therefore, a handover procedure for supporting the mobility is required even in the small cell environment that may be configured in response to the demand for the high speed and high capacity communication system.